How to make your own windshield washer fluid this winter

Anika BeaudryDigital Journalist
Published on Nov. 21, 2025, 5:21 PM

This DIY hack will help save you big bucks this winter, and you already have the ingredients at home!

Freezing rain and snow are already in the forecast across Canada this season, which means dreaded chilly mornings scraping snow and ice off the car and waiting for the windshield to defog are upon us.

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Even after all that chilly work to get your car clean and safe to drive, you still have messy roads to contend with, which means going through lots and lots of windshield washer fluid. But did you know that instead of spending your money on jugs of windshield washer fluid, you can make your own with ingredients you probably already have at home?

All you need is:

  • 4 cups water

  • ½ cup rubbing alcohol

  • 1 tsp dish soap

  • Food colouring (optional)

The rubbing alcohol will prevent the fluid from freezing during winter’s subzero temperatures, and the dish soap will help break down the dirt kicked up on the slushy roads. If you want to give the mixture the classic bright colour that comes with store-bought windshield washer fluid, you can add a couple drops of food colouring.

Don’t put the dish soap away immediately, though—you can use dish soap on the inside of your car to help prevent condensation from building up as well!

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Simply place a drop of soap on a damp cloth and wipe the inside of your car windows with it. Then, take a dry cloth and wipe away any excess water and soap. Alternatively, you can add a drop of dish soap into a spray bottle with water and use it to spray the inside of your windows instead of wiping them, but you’ll still need a dry towel to wipe off the excess soapy water.

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The soap will help to prevent water vapour from condensing on your windows. This, as well as running the air in your car, will make for a much faster defogging process, saving you time.

Thumbnail image from Getty Images, with credit to BanksPhotos.